Von Willebrand Disease (vWD) type 1 is the most common form of vWD, accounting for as much as 80% of reported cases. With prevalence estimates as high as 1.6% in the general population, upwards of 4.5 million Americans may be affected. Unfortunately vWD type 1 is also the most difficult type to diagnose, leading to greater patient distress and increased cost. The goal of the proposed study is to identify and characterize common polymorphisms within the von Willebrand factor (vWF) gene that account for a sufficient portion of variation in vWF levels to be clinically useful in the diagnosis and management of von Willebrand disease (VWD) type I. Successful execution of this project will advance the understanding of vWD by providing a strong foundation to direct future studies, and an experimental paradigm that can be used to accelerate the dissection of complex traits. The project is designed also to advance this young investigator's knowledge and skills as a nurse scientist and genetics researcher. Moreover, the methodology can be applied to any gene locus in the search for genetic causes of vWD. This research is relevant to public health, vWD type 1 is the most common bleeding disorder. In addition there has been a continued call for a more accurate method of diagnosis, as conventional methods have not proved very useful in the assessment of this particular bleeding disorder. [unreadable] [unreadable] [unreadable]